Ladder



(No Model.)

F. B. MALLORY.

LADDER.

Patented June 12, 1894.

Wl TNE SSE S L' Wyd/ stores, and of the class in which f lUNITED STATES PATENT Ormeaa FRANK B. MALLORY, lOF FLEMINGTON, NEW JERSEY.

LADDER.

SPECIFICATION forming part of Letters Patent No. 521,381, dated June 12, 1894.

Application filed October 21,1893. Serial No. 488,779. (No model.) I

To @ZZ whom it may concern: v

Be it known that I, FRANK B. MALLORY, of Flemington, in the county of Hunterdon and State of New Jersey, have invented a new and Improved Ladder, of which the following is a full, clear, and exact description. f

My invention relates to ladders for use in a track is provided for the ladder.

The object of the invention is to provide an improved means for propelling the ladder, and which may be applied to most of the ladders now 1n use.

Various means have been employed whereby a person standing on a ladder could propel the saine, such means being arranged in connection with the hanging devices of the ladder. Such devices possess the disadvantage that they cannot well be applied to the form of ladders now generally employed, and if so applied would not give the best results, as will be explained hereinafter.l

The present invention consists in the novel features hereinafter particularly described and defined in the claims.

Reference is to be had to the accompanying drawings, forming a part of this specification, in which similar letters of reference indicate corresponding parts in all the figures.

Figure l is a perspective view of a ladder and its track of the form now generally employed, showing my improvements applied thereto. Fig. 2 is a broken front view thereof; and Fig. 3 an enlarged detail sectional view of a part of the improvements.

The ladder A, comprises the side barsV a and stepsa, and to the top step the hanger bolt B is secured, the said bolt depending from a curved' carrier C, which has at its ends the rollers D, that move in and are supported on the inverted U-shaped track E, whereby the ladder is suspended from the track, the lower end of the ladder having wheels F, that rest on the floor. The parts thus far described are of a common construction now generally employed.

In connection with the ladder I provide a propelling mechanism of novel arrangement, as follows: The wheels F, are ixedly secured to the shaft G on which they are mounted, and the said shaft is extended at one side beyond the side rail a of the ladder, and on such extended end a chain wheel H, is keyed. Thus the wheels F are converted into propelling Wheels instead of being merely anti-friction wheels or rollers, asin ordinary1 ladders. The chain wheel H, is rotated in either direction by the endless chain I, which also passes over a chain wheel I-I, carried byaframe or housing J, secured to the ladder near the upper end thereofthroughthe medium of screws j,0r the like, that pass through flanges j on the frame, and engage the side bar of the ladder.

The side bars aof the ladder are iitted with boxes g for the shaft G, said boxes being tubular, extending through the said side bars, and formed each with a flange g', which fits against the inner surface of the side bar and is secured thereto by screws g2, or the like. With the arrangement shown it will be seen the ladder is suspended from the overhead track by the guide devices B, C,VD, and

in practice the weight of a person is the morev often below the center of the ladder, since it is rarely necessary to stand near thetop ofthe ladder even to reach goods adjacent to the top. The weight of the occupant of the ladder is thus eectively availed of to obtain atraction of the wheels F that will insure a propulsion of the ladder in response to the rotation of such wheels. rable and inexpensive, and they may readily be applied to ladders now in use without changing the latter.

Having thus fully described my invention, I claim as new and desire to secure by Letters Patentl. The combination with aladder, of a hanger at the upper end, running wheels at the lower end of the ladder, an endless chain extendinglongitudinallyofthe ladder, andchain wheels over which said chain travels, the lower one'of the chain wheels having a driving connection with the running wheels at the bottom of the ladder, substantially as described.

y2. The combination, with a ladder and an over-head track, of a guide at the upper end of the ladder, suspending the same from the track, propelling wheels on the lower end of the ladder, a shaft on which the .said Wheels are iixedly secured, the shaft extending at one end beyond the ladder, a chain Wheel on said extended end, a second chain wheel on the ladder near the upper end, and an end- Also the attachments are du-A less chain passing over said chain wheels, sub- I Wheel fixed to said projecting end, a second stantially as described. chain `Wheel journaled in ahousing or frame 3. Thelcoinbination, with a ladder and an having flanges secured to theladder near the over-head track therefor, of a guide at the upupper end thereof, and an endless chain pass- 15 5 per end of the ladder, suspending the same ing over said chain Wheels, substantially as from the track, bearing boxes at the bottom described. of the ladder in the side bars thereof, the boxes having flanges secured to the side bars, a shaft journaled in said boxes, having fixed Witnesses: 1o Wheels for propelling the ladder, the shaft pro- THOMAS BLOOMER,

j ecting beyond the ladder at one side, a chain JOHN G. SANDERSON.

FRANK B. MALLORY. 

